Executive Summary 1 Voter Power under First Past the Post 2 The effect of moving to the Alternative Vote 2 The VPI website 2 1. The AV Referendum in context 3 The referendum options 3 First Past the Post in the 2010 General Election 4 The effects of marginal and safe seats 4 2. The Voter Power Index 6 How the Voter Power Index is calculated 6 Voter Power under FPtP and AV 7 Numbers of marginal and safe constituencies 8 Beyond the referendum 10 Conclusion 11 Appendix 1. Summary of electoral systems 12 Appendix 2. The Voter Power Index: the statistical basis 14 Calculating the VPI for First Past the Post 14 Calculating the VPI for the Alternative Vote 15 Endnotes 18 This report examines the distribution of electoral power amongst voters in the UK and the possible impact of a change in the electoral system. It compares the distribution under the current First Past the Post system (FPtP) with the Alternative Vote system (AV) which will be put before voters in the May 2011 referendum. Our aim is to help voters consider the impact of the choice on offer in the referendum. Our analysis shows that moving from FPtP to AV will mitigate some of the distortions of the current system, but that inequalities and inefficiencies in the distribution of voter power would remain. Our research builds on nef’s 2005 report Spoiled Ballot which developed the first Voter Power Index (VPI).1 The VPI measures the power of voters to change the outcome of the election. Voter power is measured for each constituency and is determined by the chance of it changing hands and the number of voters. The more marginal and smaller the constituency, the higher the VPI score. The key findings of our analysis are that moving from FPtP to AV would produce: An increase in the average power of UK voters from 0.285 of a vote to 0.352 of a vote (where a score of 1 is a fair vote). An increase in the number of very marginal seats from 81 to 125, an increase of 44 seats. A reduction in the number of very-safe seats from 331 to 271, a reduction of 60 seats. A small reduction of inequality in the power of votes with the most powerful fifth of electors going from having 21 times the power of the least powerful fifth down to 18 times. While these improvements are significant, moving to AV will go only some way towards mitigating the unequal power of votes and the wasted votes within the British electoral system. Voter power is unevenly distributed under both systems and the fact that the average VPI score for each system is well below the ideal score of 1 suggests that neither system is very good at translating votes into electoral power. The inequality and inefficiency are caused by the use of single-member constituencies. This produces large numbers of very safe seats where votes for one party pile up into large majorities, while votes for other parties are effectively discarded. To fundamentally address these issues would require moving to larger constituencies which elect more than one member of parliament. This is not currently being considered by the Government and is not an option in the forthcoming referendum. VPI is one measure The Voter Power Index 1 among several factors to be considered when comparing different electoral systems. Voter Power under First Past the Post Our findings make two important points about voter power in the UK. First, they show that voter power is highly uneven across the country, or rather between constituencies. Under the current system of First Past the Post (FPtP), the most powerful 20 per cent of voters have 21 times as much power as the least powerful. This is the statistical reflection of a well- understood fact: it is the voters in marginal constituencies who determine the outcome of an election. Both voters and parties are well aware that some constituencies are more important than others. In election campaigns, parties spend more than twice as much in the most powerful seats as in the least. Turnout in marginals is up to 6 per cent higher than in the safest seats. At the last general election as many as a million people may have been deterred from voting because they live in safe seats. Our second finding is that the current system is inefficient in turning votes into seats. The average voter power score is only 0.285 compared to an ideal score of 1 which represents every vote counting equally towards the outcome of a general election. In the FPtP system many votes are effectively wasted because they form part of large majorities or are cast for candidates who do not win. The effect of moving to the Alternative Vote Our analysis demonstrates that switching to AV would mitigate both of these issues somewhat. Our modelling suggests that AV would increase the number of constituencies which change hands at each election: from 13 per cent to 16 per cent. This leads to a significant increase in the number of strongly contested very marginal seats: 125, up from 81. Because of this, average voter power under AV would be 0.352, compared to 0.285 under FPtP. The increase in power is proportionately greatest in the least powerful constituencies. Under AV the most powerful constituencies have 18 times the power of the least powerful – down slightly from 21 times under FPtP. Moving to AV mitigates, rather than eliminates the inequality and inefficiency of FPtP. Because AV retains the current system of small, single MP constituencies, its overall effects on the distribution of voter power are limited. By contrast, the system of large, multi-member constituencies used in the Euro-elections offers significantly higher and more even distributed voter power. British voters in the 2009 European Parliament elections had an average VPI score of 0.962.2 While the system used in the European elections is not ideal – it uses an allocation system which favours large parties and uses closed rather than open lists – this score does highlight the potential of multi-member constituency systems to significantly impact on the distribution of voter power. The VPI website In our efforts to inform the public of their voter power, nef has lent its research to web-designer Martin Petts again to develop it into a website. The website www.voterpower.org.uk provides an easy to use tool for people to see their voter power score under both FPtP and AV, assisting them to make an informed decision on the issue. The Voter Power Index 2 Across the world, free and fair elections are synonymous with democracy. They are the mechanism by which citizens select their representatives and the threat of electoral defeat is the key instrument by which citizens can control their government. The last fundamental reform of the electoral system in the UK was in 1918 when the Representation of the People Act gave women the vote. This year, for the first time, there will be a UK-wide referendum on whether there should be a change to the electoral system. On May 5 2011, UK voters will be faced with the question: At present, the UK uses the “first past the post” system to elect MPs to the House of Commons. Should the “alternative vote” system be used instead? The result will be decided by a simple majority, with every vote cast in England, Northern Ireland, Scotland and Wales counting equally. UK-wide referenda are very rare. The last one was the 1975 referendum on the UK’s membership of the European Community. This short report aims to help voters consider the alternatives available to them on May 5. It presents a statistical analysis of the power that the two systems on offer in the referendum would give voters have across the UK. The report builds on nef‘s 2005 report Spoiled Ballot which highlighted the uneven distribution of voter power between electors in the UK. The report introduced the Voter Power Index (VPI), which is a measure of the power of an individual vote to influence the composition of parliament. For this report the VPI has been recalculated and a new comparable AV-VPI (Alternative Vote Voter Power Index) has been created to estimate the power that voters would have if the Alternative Vote (AV) system was adopted. VPI is one measure among several factors to be considered when comparing different electoral systems. The referendum options The referendum offers voters only two options – to retain the current First Past the Post (FPtP) system or to switch to a new system, the Alternative Vote (AV)..FPtP and AV differ in the way votes are cast and counted but both would retain the current constituency boundaries. There are approximately 44 million registered electors in the UK divided into 650 constituencies. Each constituency elects its one member of parliament (MP). Legislation that was passed at the same time as the Referendum Bill demands a re-drawing of the boundaries to move to 600 single-member constituencies but this is not the subject of this referendum or our analysis. The Voter Power Index 3 Under the current electoral system the candidate with the most votes in each constituency is elected to the House of Commons at Westminster to represent all the voters within the constituency. The current system is commonly referred to as ‘First Past the Post’ as the winning candidate simply has to get more votes than any other candidate. Under the AV system voters are given the opportunity to rank the candidates in order of their preferences.